Various heat exchanger tube spacing devices are currently in use. For example, it is specified in USSR Inventor's Certificate No. 1556253 (issued on Jan. 15, 1994), Russian Patent No. 2153643 (issued on Jul. 27, 2000) and Russian Utility Model Patent No. 6224 (issued on Mar. 16, 1998) that tubes of the heat exchanger bundle are bound by profiled plates (dividers) which are rather difficult to make.
Its closest analogue is a heat exchanger tube spacing device described in USSR Inventor's Certificate No. 515025 (issued on May 25, 1976). This device includes a supporting spacer grid which consists of two round-shaped coaxial cylindrical shells connected by an intermediate ring; each shell is provided with sleeves used to run the aforementioned heat exchange tubes through them; these sleeves are spaced apart at a preset gap and are bound with bridges, while sleeves of both shells are aligned in corners of equiangular triangles when observing along the shell axis. Russian Patents No. 2384807 (issued on Mar. 20, 2010) and No. 2386915 (issued on Apr. 20, 2010) describe similar solutions.
USSR Inventor's Certificate No. 400797 (issued on Oct. 1, 1973) by V. S. Neevin, S. G. Khachaturyan, L. A. Dolgy, N. A. Georgiyevsky, D. I. Isbatyrov is known where a spacer grid was made of a solid piece, while its cells were mostly formed by milling cut.
Reliability of fixation of heat exchanger tubes in such devices, especially under the effect of corrosion, vibration and high temperatures, is obviously insufficient due to the fact that sleeves of different shells are not interconnected, and the fixation of heat exchanger tubes in radial axis is not secure.